openclaw/src/terminal/stream-writer.ts
2026-01-21 03:03:29 +00:00

65 lines
1.6 KiB
TypeScript

export type SafeStreamWriterOptions = {
beforeWrite?: () => void;
onBrokenPipe?: (err: NodeJS.ErrnoException, stream: NodeJS.WriteStream) => void;
};
export type SafeStreamWriter = {
write: (stream: NodeJS.WriteStream, text: string) => boolean;
writeLine: (stream: NodeJS.WriteStream, text: string) => boolean;
reset: () => void;
isClosed: () => boolean;
};
function isBrokenPipeError(err: unknown): err is NodeJS.ErrnoException {
const code = (err as NodeJS.ErrnoException)?.code;
return code === "EPIPE" || code === "EIO";
}
export function createSafeStreamWriter(options: SafeStreamWriterOptions = {}): SafeStreamWriter {
let closed = false;
let notified = false;
const noteBrokenPipe = (err: NodeJS.ErrnoException, stream: NodeJS.WriteStream) => {
if (notified) return;
notified = true;
options.onBrokenPipe?.(err, stream);
};
const handleError = (err: unknown, stream: NodeJS.WriteStream): boolean => {
if (!isBrokenPipeError(err)) {
throw err;
}
closed = true;
noteBrokenPipe(err, stream);
return false;
};
const write = (stream: NodeJS.WriteStream, text: string): boolean => {
if (closed) return false;
try {
options.beforeWrite?.();
} catch (err) {
return handleError(err, process.stderr);
}
try {
stream.write(text);
return !closed;
} catch (err) {
return handleError(err, stream);
}
};
const writeLine = (stream: NodeJS.WriteStream, text: string): boolean =>
write(stream, `${text}\n`);
return {
write,
writeLine,
reset: () => {
closed = false;
notified = false;
},
isClosed: () => closed,
};
}